Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland
Spatial and temporal variability in population densities and relative (length- specific) condition of Adantic salmon parr in Harry's River were examined over the period 1987-1997. Apparent differences in growth allometry (slopes from log weight: log forklength regression) among sites and years...
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Memorial University of Newfoundland
1999
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ftmemorialuniv:oai:research.library.mun.ca:839 2023-10-01T03:54:48+02:00 Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland Fitzgerald, Jennifer 1999 application/pdf https://research.library.mun.ca/839/ https://research.library.mun.ca/839/1/Fitzgerald_Jennifer.pdf https://research.library.mun.ca/839/3/Fitzgerald_Jennifer.pdf en eng Memorial University of Newfoundland https://research.library.mun.ca/839/1/Fitzgerald_Jennifer.pdf https://research.library.mun.ca/839/3/Fitzgerald_Jennifer.pdf Fitzgerald, Jennifer <https://research.library.mun.ca/view/creator_az/Fitzgerald=3AJennifer=3A=3A.html> (1999) Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland. Masters thesis, Memorial University of Newfoundland. thesis_license Thesis NonPeerReviewed 1999 ftmemorialuniv 2023-09-03T06:44:06Z Spatial and temporal variability in population densities and relative (length- specific) condition of Adantic salmon parr in Harry's River were examined over the period 1987-1997. Apparent differences in growth allometry (slopes from log weight: log forklength regression) among sites and years were attributable to variability in stomach contents of the smaller fish and to sex and maturity status of the largest fish. Pooling of all weight: length data permitted identification of significant differences in relative condition factors (weight: length regression intercepts for specific sites/years) among all sites and years. No significant correlations were found between site-specific relative condition and parr density, food availability or physical habitat factors. The lack of correlation may be due to differences in the scale of the prey measurements versus parr feeding ranges. -- A large proportion of males in the tributaries were sexually mature or "precocious" which corresponded with a preponderance of females (71%) in returning anadromous adults. There was a clear trend for increasing percentage male composition in the streams with age and even at age 1+ more than half of the males were precociously mature. The declining proportion of females with increasing age class in the streams suggests that females made greater use of pond habitat than males. Precociously maturing males had higher mean fork lengths and mean weights than immature males at age 1+ but growth rates decreased in the older age classes. The relative length-specific condition of precocious male parr was significantly higher than that of immature male and female parr at ages 1+ and 2+ while relative length-specific condition of 3+ female parr was very close to that of precocious males, indicating increased weight gain for females prior to smoltification. -- Discriminant analysis was employed to construct a model that would predict sex and maturity status from the easily measured variables length and weight, and from length-specific condition ... Thesis Atlantic salmon Newfoundland Salmo salar Memorial University of Newfoundland: Research Repository |
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Memorial University of Newfoundland: Research Repository |
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ftmemorialuniv |
language |
English |
description |
Spatial and temporal variability in population densities and relative (length- specific) condition of Adantic salmon parr in Harry's River were examined over the period 1987-1997. Apparent differences in growth allometry (slopes from log weight: log forklength regression) among sites and years were attributable to variability in stomach contents of the smaller fish and to sex and maturity status of the largest fish. Pooling of all weight: length data permitted identification of significant differences in relative condition factors (weight: length regression intercepts for specific sites/years) among all sites and years. No significant correlations were found between site-specific relative condition and parr density, food availability or physical habitat factors. The lack of correlation may be due to differences in the scale of the prey measurements versus parr feeding ranges. -- A large proportion of males in the tributaries were sexually mature or "precocious" which corresponded with a preponderance of females (71%) in returning anadromous adults. There was a clear trend for increasing percentage male composition in the streams with age and even at age 1+ more than half of the males were precociously mature. The declining proportion of females with increasing age class in the streams suggests that females made greater use of pond habitat than males. Precociously maturing males had higher mean fork lengths and mean weights than immature males at age 1+ but growth rates decreased in the older age classes. The relative length-specific condition of precocious male parr was significantly higher than that of immature male and female parr at ages 1+ and 2+ while relative length-specific condition of 3+ female parr was very close to that of precocious males, indicating increased weight gain for females prior to smoltification. -- Discriminant analysis was employed to construct a model that would predict sex and maturity status from the easily measured variables length and weight, and from length-specific condition ... |
format |
Thesis |
author |
Fitzgerald, Jennifer |
spellingShingle |
Fitzgerald, Jennifer Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
author_facet |
Fitzgerald, Jennifer |
author_sort |
Fitzgerald, Jennifer |
title |
Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
title_short |
Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
title_full |
Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
title_fullStr |
Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
title_full_unstemmed |
Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland |
title_sort |
temporal and spatial variability in density, relative condition, gender composition and maturity status of atlantic salmon (salmo salar l.) parr in the harry's river drainage system, insular newfoundland |
publisher |
Memorial University of Newfoundland |
publishDate |
1999 |
url |
https://research.library.mun.ca/839/ https://research.library.mun.ca/839/1/Fitzgerald_Jennifer.pdf https://research.library.mun.ca/839/3/Fitzgerald_Jennifer.pdf |
genre |
Atlantic salmon Newfoundland Salmo salar |
genre_facet |
Atlantic salmon Newfoundland Salmo salar |
op_relation |
https://research.library.mun.ca/839/1/Fitzgerald_Jennifer.pdf https://research.library.mun.ca/839/3/Fitzgerald_Jennifer.pdf Fitzgerald, Jennifer <https://research.library.mun.ca/view/creator_az/Fitzgerald=3AJennifer=3A=3A.html> (1999) Temporal and spatial variability in density, relative condition, gender composition and maturity status of Atlantic salmon (Salmo salar L.) parr in the Harry's River drainage system, insular Newfoundland. Masters thesis, Memorial University of Newfoundland. |
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thesis_license |
_version_ |
1778522739388186624 |